THORACIC AND CRANIAL RADIOTHERAPY FOR LIMITED-STAGE SMALL-CELL LUNG-CANCER

Chemotherapy remains the mainstay of treatment for small cell lung can cer (SCLC). For patients with limited-stage disease, the addition of t horacic radiotherapy confers a moderate improvement in local control a nd a modest survival benefit, but these improvements come at the cost of increased toxic reactions. The optimal method for integrating chemo therapy and thoracic radiotherapy is unresolved, Concurrent and altern ating strategies are appealing because they allow uninterrupted delive ry of chemotherapy, but they have not been proven to be superior to co nventional sequential approaches. Based on limited data, delivery of t horacic radiation early in the treatment course may be preferable to d elivery later in the course. There is evidence of a radiation dose-res ponse effect for SCLC, and, in standard regimens, thoracic radiation d oses in the range of 50 to 60 Gy are recommended. The use of limited r adiation fields (to postchemotherapy tumor volumes) appears reasonable , Results for alternative thoracic radiation fractionation schedules s uch as accelerated hyperfractionation are promising and worthy of furt her investigation. The role of prophylactic cranial irradiation (PCI) is controversial and should be individualized. It should be considered for the favorable subgroup of patients with limited-stage disease who achieve a complete response to chemotherapy and thoracic radiotherapy . If given, we recommend a total dose of 30 to 36 Gy in 2-Gy fractions ; PCI should not be delivered concomitantly with chemotherapy.